Process for preparing unsaturated chlorohydrocarbons and saturated polychlorohydrocarbons by oxychlorination of hydrocarbons and catalyst system therefor

ABSTRACT

1. A process for the preferential oxychlorination of ethane and/or ethyl chloride as a reactant to form 1,2-dichloroethane as the major reaction product, which comprises feeding the reactant ethane and/or ethyl chloride in the vapor phase in admixture with hydrogen chloride in an amount within the range from about 0.05 to about 5 equivalents per mole of the reactant and with molecular oxygen in an amount within the range from about 0.2 to about 1.5 moles per equivalent of hydrogen chloride in contact with a catalyst consisting essentially of a copper chloride and a Group II b metal chloride in an amount within the range from about 20 to about 70 mole percent based on the moles of copper, at a temperature within the range from 250* to 400*C, and recovering 1,2-dichloroethane as the major reaction product.

United States Patent [191 UNITED STATES PATENTS 3,267,162 8/1966 Bohl260/659 A 3,190,931 6/1965 Laine et a1, ..260/659 A Pritchett 1March 13,1973 5 1 PROCESS FOR PREPARING 2,957,924 10/1960 Heiskell et al...260/659 A UNSATURATE iiiil? 1111323 If" i" "323223 A eat ers et a A gfggfgg AND 2,838,577 6/1958 Cook et a1. 260/656 R POLYCHLOROHYDROCARBONSBY FOREIGN PATENTS OR APPLICATIONS 677,714 I/1964 Canada ..260/659 ASYSTEM THEREFOR Primary Examiner-I-loward T. Mars [75] Inventor: ErvinG. Pritchett, Cincinnati, Ohio Assistant Examiner JoSePh BoskaAttorney-Allen A. Meyer, Jr. [73] Assignee: National Distillers andChemical Corporation, New York, NY. EXEMPLARY CLAIM 1 1 Filed: 1969 1. Aprocess for the preferential oxychlorination of [2}] App. N0: 876 187ethane and/or ethyl chloride as a reactant to form 1,2-

dichloroethane as the major reaction product, which Related US.Application Data comprises feeding the reactant ethane and/or ethylchloride in the vapor phase in admixture with [63] 58x21 of 1966hydrogen chloride in an amount within the range from about 0.05 to about5 equivalents per mole of the reactant and with molecular oxygen in anamount [52] CL "260/658 260/656 260/659 within the range from about 0.2to about 1.5 moles per equivalent'of hydrogen chloride in contact with acatalyst consisting essentially of a copper chloride and 1 a Group 11 bmetal chloride in an amount within the range from about 20 to about 70mole percent based [5.6] References cued on the moles of copper, at atemperature within the range from 250 to 400C, and recovering 1,2-dichloroethane as the major reaction product.

11 Claims, No Drawings PROCESS FOR PREPARING UNSATURATEDCHLOROHYDROCARBONS AND SATURATED POLYCHLOROHYDROCARBONS BYOXYCHLORINATION F HYDROCARBONS AND CATALYST SYSTEM THEREFOR Thisapplication is a continuation of copending application Ser. No. 529,899,filed Jan. 3, 1966, now abandoned.

This invention relates to a process and catalyst system for theoxychlorination of hydrocarbons, so as to form unsaturatedchlorohydrocarbons and saturated polychlorohydrocarbons, and moreparticularly to a process for the oxychlorination of ethane to producepreferentially vinyl chloride and 1,2-dichloroethane, using as thecatalyst therefor copper chloride in combination with a Group 11b metalchloride.

The chlorination of lower aliphatic hydrocarbons and benzene as well astheir partly chlorinated products, using a mixture of hydrogen chlorideand oxygen or an oxygen-containing gas such as air are referred to asoxychlorination reactions. In these processes, the material to bechlorinated is reacted in the vapor phase with gaseous hydrogen chlorideand oxygen over a suitable metal chloride catalyst at elevatedtemperatures up to about 700C.

In contrast to chlorination processes, which are costly because theyrequire chlorine gas, oxychlorination processes can be carried out usinghydrogen chloride, which is available in many manufacturing complexes asa by-product of other processes. As a starting material, saturatedhydrocarbons are certainly preferable to olefinic hydrocarbons, such asethylene, because olefins normally are derived from the saturatedhydrocarbons by cracking, which requires a separate step. However, inthe oxychlorination processes which have been provided heretofore,olefins have been the preferred materials, because they react readilyand in high yield, undergoing simple addition with the hydrogenchloride, whereas saturated hydrocarbons have given only poor yields,probably because they can react only via difficult substitution routes.Thus, for example, the addition of chlorine to ethylene directly yields1,2-chloroethane, evenly and in high yield, whereas up until now, it hasnot been possible to prepare his chloro hydrocarbons from ethane in anyreasonable yield, using available oxychlorination catalysts andprocesses.

Thus, for example, U.S. Pat. No. 2,807,656 patented Sept. 24, 1957 toCherniavsky, and British Pat. No. 635,013 published Mar. 29, 1950,describe processes for the production of saturated and unsaturatedhalogenated hydrocarbons from alkenes. The process of British Pat. No.635,013 yields both vinyl halides and ethyl halides from the unsaturatedhydrocarbons. As the catalysts, halides or oxyhalides of zinc. aluminum,bismuth, antimony, iron and vanadium are employed. A typical first stagereaction product in the Example is obtained from a reaction carried outat 440C. without a catalyst, and contains 9.1 mol percent of vinylchloride and 2.3 mol percent of ethylene dichloride, with 72 mol percentof ethylene. This is reacted with more HCI, after removal of vinylchloride, over a catalyst of copper chloride and zinc chloride at 190C.,to give a product composed of 16.3 mol percent of ethyl chloride, 2.3mol percent ethylene dichloride and 77.7 mol percent of unreactedethylene. These are rather low yields of ethylene dichloride.

The process of U.S. Pat. No. 2,807,656 is carried out using zincchloride as the chlorination catalyst, with a promoter such as copper,lithium, antimony, magnesium, calcium, bismuth and the like, underconditions such that the ethane is substantially inert, and the ethylenereacts with hydrogen chloride to form ethyl chloride, unreacted ethane,and a minimum of byproducts. A typical reaction, according to Example 1,resulted in a percent conversion of ethylene, with a 99.5 percent yieldof ethyl chloride, based on the amount of ethylene converted. None ofthe examples shows the formation of dichlorinated products in anysignificant amount.

U.S. Pat. No. 2,407,828, patented Sept. 17, 1946, to Gorin, describesthe oxychlorination of saturated hydrocarbons such as methane andethane, using a cupric chloride-containing salt melt. The cupricchloride is obtained by the reaction of cuprous chloride with halogenacid gas and an oxygen-containing gas. The resulting cupric halide meltis then transferred to a separate reaction zone, wherein it is contactedwith a counterflow of hydrocarbon gases or vapors, thereby forming thecorresponding alkyl or aryl halides, and reforming cuprous chloridetherein. A minor proportion of potassium chloride can be included in thecatalyst, together with other halides of Groups I, 11, 111 and IV of thePeriodic System having molecular weights greater than copper, such aslead, zinc, silver and thallium, which can be used in place of ortogether with the alkali metal halides.

The principal reaction product of this process is the primary halide,but small amounts of dihalides, unsaturated halides and olefins can beformed. In Example 4 a product is obtained composed of 60.3 mol percentof ethylchloride, 2.8 mol percent of ethylene, 24.6 mol percent ofethylene dichloride, 5.6 mol percent of ethylene monochloride, 3.3 molpercent of ethylene trichloride, and 3.4 mol percent of ethylenetetrachloride. However, only 30.2 mol percent of the ethylene gas hadreacted in this procedure, using copper chloridepotassium chloride saltmelt at 445C.

French Pat. No. 1,326,738 Apr. 1, 1963, describes the preparation ofethylenically unsaturated chlorinated hydrocarbons from aliphatichydrocarbons or chlorohydrocarbons, using hydrogen chloride and acatalyst composed of cupric chloride, zinc chloride and potassiumchloride. The composition of a typical product shown in Table II was70.4 percent of vinyl chloride, 12.5 percent of ethylene dichloride, 4.7percent ethylene trichloride, 4.0 percent of ethyl chloride, and theremainder, a mixture of halogenated methanes. This reaction was carriedout at 500C., using a catalyst composed of copper chloride, potassiumchloride and zinc chloride.

The high operating temperatures required in most prior oxychlorinationprocesses has led to a number of difficulties. At high temperatures, thehydrogen chloride fed tends to increase "corrosion and handlingproblems, both during the reaction and in separating unreacted hydrogenchloride from the product stream. Moreover, at high reactiontemperatures, the metal halide oxychlorination catalysts show aconsiderable volatility, and tend to be entrained in the product stream,these losses increasing the cost of operation and separation. At hightemperatures, the oxygen present in the stream can also react with thehydrocarbons and their partly chlorinated products, leading toconsiderable losses, due to burning to carbon oxides and water.Localized hot spots within the catalyst bed may also occur, givingdifficulties in controlling the reactor temperature, and leading toserious decompositions and increased yields of by-products in theseportions of the reaction mixture.

It would accordingly be preferable to carry out oxychlorinationprocesses at rather low reaction temperatures, but unfortunately thishas not been possible. The oxychlorination of saturated hydrocarbons inparticular has required very high reaction temperatures. For example,the direct oxychlorination of ethane to vinyl chloride requires atemperature of about 500C. At lower reaction temperatures, there is achange in product distribution to favor saturated chlorohydrocarbons,and at temperatures below about 450C. ethyl chloride replaces vinylchloride as a major product. Unfortunately, losses both by burning anddifficulties with catalyst volatility increase rapidly above 400C.

In order to reduce catalyst volatility at high reaction temperatures, ithas been proposed that the catalyst be diluted by the addition of metalhalides of lower volatility, or which will form double salts with thecatalyst halides and so reduce volatility. For example, potassiumchloride, as described in French Pat. No. 1,326,738 and in U.S. Pat. No.2,407,828, has been incorporated for this purpose. However, it has beendetermined in accordance with the instant invention that in theoxychlorination of ethane, for example,

potassium chloride deleteriously affects the reaction productdistribution, and leads to the production of an increased proportion ofethyl chloride in the product stream at the expense of vinyl chlorideand 1,2- dichloroethane, which is readily convertible to vinyl chloride.Even at very high hydrogen chloride feeds, such as about threeequivalents or more per mole of reactant to be chlorinated, productdistributions in ethane oxychlorination tend to favor ethyl chlorideunder these conditions, particularly at desirably high conversions ofethane to chlorinated products.

In accordance with the instant invention, lower saturated aliphatichydrocarbons and chlorohydrocarbons are oxychlorinated preferentially tounsaturated chlorohydrocarbons and saturated polychlorohydrocarbons,employing as the oxychlorination catalyst a mixture of copper chlorideand a chloride of a Group IIb metal, in the presence of hydrogenchloride and oxygen. This process is capable of producing high yields ofthe preferred chlorinated hydrocarbons, at reaction temperatures belowabout 450C. and a feed ratio of chlorinating agent to reactantconsiderably less than about three equivalents of chlorinating agent permole of reactant. Under these conditions, only minor amounts ofsaturated monochlorohydrocarbons are obtained.

The invention further provides an oxychlorination catalyst for use inany oxychlorination process consisting essentially of copper chloride incombination with a Group lIb metal chloride as cocatalyst. As the GroupIIb metal, 'zinc is preferred, but there can also be employed chloridesof cadmium and mercury. Both cuprous and cupric chlorides can be used.Any cuprous chloride at the start of the reaction will be converted tocupric chloride under the oxidation conditions of the process, in thepresence of oxygen and hydrogen chloride, and the cuprous chlorideformed as a reaction product of the oxychlorination also is convertedback to cupric chloride under the reaction conditions. Similarly, bothmercurous and mercuric chloride can be employed, as well as zincchloride and cadmium chloride.

The relative proportions of copper chloride and Group IIb metal chlorideof the catalyst are not critical. Satisfactory proportions of Group Ilbchloride range from about 20 to about mol percent, preferably from about30 to about 60 mol percent, based on the moles of copper chloridepresent.

The catalyst also can be prepared in situ from a mixture of any compoundof copper and any compound of a Group IIb metal that is convertibleunder the oxychlorination conditions to the corresponding metalchlorides. Thus, for instance, oxides of the metal can be used, as wellas nitrites, nitrates, sulfites, sulfates, phosphates, acetates,oxalates, formates, cyanides, borates, carbonates and hydroxides.

In addition to the copper chloride and Group IIb metal chloride, thecatalyst composition can include a chloride of a metal other than analkali metal which reduces volatility of the catalyst system under theoxychlorination conditions. Such halides include, among others, halideswhich are capable of forming double or triple salts with the othercatalyst components, or which have a lower volatility than the othercatalyst components, and consequently reduce the volatility for one orboth of these reasons. Typical halides in this group which do not have adeleterious effect upon selectivity of the catalyst include magnesiumchloride, barium chloride, strontium chloride, calcium chloride, leadchloride and cerium chloride. 1

A convenient method for preparing the catalyst from the correspondingchloride is to mix a copper chloride such as cupric chloride with aGroup IIb metal chloride in common solution, preferably an aqueoussolution, but organic solvent solutions can also be used, andsubsequently evaporate the solvents used, thereby forming acoprecipitate of the two chlorides as a homogeneous mixture. Granules orparticles thus obtained can be composed of the mixed salts, or ofcocrystallized salts. Double decomposition reactions to form the saltscan also be carried out in such solutions, for instance, reaction of theoxides or hydroxides in aqueous hydrochloric acid solution to form thechlorides upon removal of the water solvent.

In order to facilitate the process of the invention, by exposing as higha surface area of the catalyst as possible, it is preferred that thecatalyst be deposited on a suitable support. However, a support is notessential, and can be omitted.

When a support is used, the total concentration of copper expressed ascupric chloride should be within the range from about 0.1 to about 25weight percent, and preferably from about 1 to about l5 weight percent,based on the weight of the catalyst support. Satisfactory supports arethe various forms of alumina, such as a-alumina, titania, zirconia,silica, pumice, carbon and other known catalyst carrier materials. Thecarrier materials should be inertunder the oxychlorination reactionconditions. Those skilled in the art will perceive what supports can beemployed from the preceding description. Especially preferred arecatalyst supports having a high surface area, and preferably having asurface area greater than about 1 square meter per gram, in order toafford maximum contact of the reactants with the catalyst.

The average particle size of the catalyst, whether or not it issupported, is chosen according to the reactor design. For fixed bedoperations, in large-size equipment, large-size particles, such asone-eighth inch tablets or spheres, are preferable. Catalysts for use influid bed operations are preferably finely-divided, such as for examplefrom 100 to 200 mesh in size. When the catalyst is supported, thesupport that is employed has a particle size that is within the statedranges, so that the support after impregnation with the catalyst neednot be further subdivided, thus disturbing the surface layer of catalyston the support.

The catalyst is applied to the support by conventional techniques.Usually, the support is immersed in a common solution of the catalystcompounds, and the solvent is then evaporated, depositing the catalyston the surface of, and within the pores of, the support.

Potassium chloride and other alkali metal chlorides are definitelydeleterious to the catalyst systems of the invention, and are notemployed. They upset the catalyst selectivity and consequentdistribution of the halogenated products obtained, so that unsaturatedmonochlorides such as vinyl chloride and saturated dichlorides, such asethane dichlorides, are obtained in very low yields, if at all. It willconsequently be under'stood that the term consisting essentially of, asemployed in the specification and claims, is intended to exclude thematerials which deleteriously affect catalyst selectivity, and isspecifically intended to exclude alkali metal halides, such as potassiumchloride.

The process of the invention is carried out by passing over thecatalyst, at a temperature at which the oxychlorination proceeds, thesaturated aliphatic hydrocarbon or chlorohydrocarbon on the vapor phasetogether with the hydrogen chloride gas and oxygen, resulting inpreferential formation of the unsaturated chlorohydrocarbon andsaturated polychlo'rohydrocarbon.

The process will proceed under a great variety of reaction temperaturesand pressures. Temperatures of within the range of about 200 to about450C. and preferably from about 250 to about 400C., will give excellentyields of the desired products. It is preferred to operate the processat or near atmospheric pressure, but both superatmospheric andsubatmospheric can be employed, if desired. Thus, the reaction pressurecan lie within the range from about 0.5 mm. up to about 200 atmospheres,but preferably lies within the range from about mm. to about 2atmospheres.

The ratios of the reactants are stoichmetrically selected to give thedesired reaction products, plus a small excess, if desired. Largeexcesses of the chlorinating agent, hydrogen chloride, can be employedif desired, and very small proportions also can be used, if a relativelysmall conversion of the saturated hydrocarbon can be accepted.

Thus, for example, the chlorinating agent, hydrogen chloride, can beemployed in a proportion within the range from about 0.05 to about 5equivalents for each mole of saturated hydrocarbon to be chlorinated.However, it is preferred to employ an amount from within the range ofabout 0.1 to about 1 equivalent per mole. At low feed ratios of thehydrogen chloride, the excess hydrocarbon feed serves as a diluent forthe oxychlorination reaction, and does not upset the distribution of thedesired reaction product.

The proportion of oxygen also can be widely varied. Amounts within therange from about 0.2 to about 1.5 moles of molecular oxygen perequivalent of chlorinating agent can be used. Oxygen itself or anyoxygen-containing gas can be employed, but it is preferred that anycomponents of the gas other than oxygen be inert to the reaction. Air isa completely satisfactory oxygen-containing gas. There can also beemployed mixtures of oxygen and nitrogen, mixtures of oxygen and helium,mixtures of oxygen and carbon dioxide, mixtures of oxygen and argon, andmixtures of oxygen and chlorinated methanes such as carbon tetrachlorideand chloroform.

Preferably, the amount of oxygen is within the range from about 0.5 toabout l mole per equivalent of hydrogen chloride. An excess of oxygenover the stoichiometric 0.5 mole per equivalent of hydrogen chloride isgenerally beneficial to the conversion and yield in the oxychlorinationreaction of the invention.

The feed rate of the reaction mixture should permit a superficialresidence time in the catalyst bed within the range from about 0.1 toabout 50 seconds. A residence time from about 0.5 to about 20 seconds isgenerally adequate, and is preferred, for optimum yield in a minimumtime. However, the feed rate chosen will of course depend upon thereaction temperature, the reactant feed ratios, and the particularhydrocarbon or chlorinated hydrocarbon reactant in the oxychlorination.The optimum feed rates for any given set of reaction conditions canreadily be determined empirically.

The process of the invention is applicable to any lower saturatedaliphatic hydrocarbon or chlorinated saturated aliphatic hydrocarbonhaving from one to about 10 carbon atoms. The process is of particularapplication to ethane, but it is also applicable to ethyl chloride andlike monoor poly-chlorinated saturated aliphatic hydrocarbons. Typicalhydrocarbons to which the process can be applied include, in addition toethane and ethyl chloride, methane, propane, 1- chloropropane,1,2-dich1oropropane, butane, lchlorobutane, l,4-dichlorobutane,l-chloro-Z-methylpropane, secondary butyl chloride, isopropyl chloride,pentane, l-chloropentane, isoamyl chloride, tertiary amyl chloride,secondary amyl chloride, 1,3,5- trichloropentane, l-chlorohexane,hexane, isohexyl chloride, heptane, heptyl chloride, 2-ethylheptylchloride, Z-ethylhexane, 2-ethylhexylchloride, octane, isooctane,nonane, decane, and l-chlorodecane.

The following Examples in the opinion of the inventors representpreferred embodiments of their invention.

EXAMPLE 1 A series of catalysts was prepared for comparison purposes,all based on cupric chloride, with additions of potassium chloride, zincchloride and cadmium chloride. The catalysts were prepared by identicalprocedures, and supported on a-alumina.

The cit-alumina used as the support for these catalysts was preparedfrom 10 to 20 mesh n-alumina (Alu- -minum Company of America, Grade F-l,meshed to size on standard screens.) This was heated for 16 hours atabout 1200C. in an electric oven. An analysis by X- ray showed theproduct to be a-alumina.

To the alumina, in a suitable round-bottom flask, was added rapidly asolution of the catalyst. In the case of Catalyst A, the solution wascomposed of 3 parts of cupric chloride in 250 parts of water, added to97 parts of the 10 to 20 mesh a-alumina. In the case of Catalyst B, thesolution was a mixture of 3 parts of cupric chloride and 1.75 parts ofpotassium chloride, deposited from aqueous solution on 95 .3 parts ofthe aalumina. In the case of Catalyst C, the solution was composed of amixture of 3 parts cupric chloride and 3 parts zinc chloride, depositedfrom common aqueous solution on 94 parts of the a-alumina. In the caseof Catalyst D, the solution was composed of 3 parts of cupric chlorideand 4.1 parts of cadmium chloride, deposited on 92.9 parts of thea-alumina.

After the catalyst solution and a-alumina had been thoroughly mixed, theround bottom flask was attached to a Labline Rotovak, and water wasremoved at a vacuum of about 20 mm. of mercury, first at roomtemperature and finally at 90C., to produce 100 parts of the supportedcatalyst.

As the reactor, there was used a 14 mm. internal diameter glass tubeabout 15 inches long, equipped with a 4 mm. outside diameter thermowell.The reactor was packed with a k inch glass wool plug, a 5 inch packingof the 10 to mesh 'q-alumina (to act as a pre-heater for reactivegases), 10 grams of the sup ported catalyst, and another A inch glasswool plug. The packed reactor was placed in a vertical tube furnace,pre-heater packing up, care being taken to hold the packed bed withinthe heated area of the furnace. To the bottom of the reactor wasattached a U-tube sample collector. During the process this was cooledto about minus 80C. in a suitable bath. A water-spray scrubber followedthe cold bath, to remove unused hydrogen chloride from the uncondensedexit gases.

In each test run, with the tube furnace-heated to 375C., a mixture ofethane (0.13 mol per hour), hydrogen chloride (0.065 mol per hour) andoxygen (0.0325 mol per hour) was passed into the top of the reactor atabout 1 atmosphere pressure. Exit gases condensed in the samplecollector over a timed period (normally one hour), were diluted with atleast 10 volumes of decalin, and analyzed via vapor phasechromatography. The mole ratios of the reaction products is shown inTable I which follows:

Chloride The test data shows the importance of the zinc .chloride andcadmium chloride in directing the oxychlorination towards the formationof vinyl chloride and 1,2-dichloroethane, and suppressing formation of,ethyl chloride. In the absence of the zinc of cadmium chloride (CatalystA) 18 millimoles per hour of ethyl chloride are produced, and only 0.7millimole per hour of 1,2-dichloroethane. Addition of potassium chlorideincreases the proportion of ethyl chloride to 31 millimoles per hour,and decreases the formation of 1,2- dichloroethane to 2.6 millimoles perhour (Catalyst B). In the presence of zinc chloride, however, 11.7millimoles per hour of l,2-dichlorocthane are obtained,

and only 1.2 millimoles per hour of ethyl chloride. Cad mium chloride issomewhat less active than zinc I chloride, but the proportion of1,2-dichloroethane is 7.6 millimoles per hour as compared to 6.2millimoles per hour of ethyl chloride, a considerable improvement overCatalysts A and B. The ratios show that the improvement in the case ofCatalyst C is 33 fold, and in the case of Catalyst D, fourfold.

Examples 2 to 6 A series of catalyst systems was prepared, containingdiffering proportions of zinc chloride to cupric chloride. Thesecatalyst systems were tested, using the apparatus and procedure ofExample 1, on ethane. The total cupric chloride remained at 3 percent ofthe total catalyst and support in each composition. The results obtainedare shown in Table II.

It is evident from the data that optimum conversion of ethane to1,2-dichloroethane is obtained at from about 50 to 60 mole percent ofzinc chloride in the catalyst. A significant improvement in 1,2-dichloroethane formation is shown starting at 9 mole percent dichloride,and even at 75 mole percent of zinc chloride, 1,2-dichloroethane isformed preferentially to ethyl chloride, but at this molar ratio theoverall conversion is reduced. The data taken as a whole shows that goodyields of 1,2-dichloroethane are obtained with catalysts having fromabout 20 to about mol percent of zinc chloride. Optimum conversion tovinyl chloride is shown at the same ratios.

Example 7 Catalysts based on combinations of cupric chloride and zincchloride and cupric chloride and potassium chloride were prepared forpurposes of comparison. The catalyst support used for these catalystsanalyzed 81.2 percent A1 (almost completely alpha, by X-ray analysis)and 17.2 percent SiO had a surface area of 20 square meters per gram,and was in the form of oneeighth inch pellets. Onto 94 parts of thesupport was deposited a mixture of 3 parts cupric chloride and 3 partszinc chloride from a common aqueous solution, and the latter wasevaporated to furnish 100 parts of supported catalyst.

As a control, a similar catalyst was prepared by adding 95.3 parts ofthe same pellets to an aqueous solution of 3 parts cupric chloride and1.7 parts of potassium chloride and 200 parts of water.

The water was evaporated, using the procedure of Example 1, to furnish100 parts of catalyst in each case.

The reactor used was a glass tube 21 mm. internal diameter and incheslong, equipped with a 4 mm. outside diameter thermowell, packed with 28grams of supported catalyst, using h inch glass wool plugs to hold thebed in place. The reactor was mounted in the same manner as Example 1,and the same oxychlorination procedure was followed as in Example 1, atthe temperatures shown in Table III, which follows:

Table III Applied Reactor Tem.,C.: 300 325 350 375 Maximum InternalTemp.,C.:

Control (KCl Cocatalyst) 303 345 380 400 Example 7 (ZnCl, Cocatalyst)Mole Ratio of CICH,CH,CI

Control (KCl Cocatalyst) 0.06 0.13 0.13 0.17 Example 7 (ZnCl,Cocatalyst) l 5.8 73. 31. 28.

It is evident from the data that the cupric chloridepotassium chloridecatalyst gave very low yields of 1,2- dichlorethane and vinyl chloride,as compared to ethyl chloride. Marked increases, to more than 500 fold,were observed when zinc chloride was substituted for the potassiumchloride, showing the effect of the potassium chloride in suppressingthe desired 1,2- dichloroethane and vinyl chloride production. Themarked effectiveness of the copper chloride-zinc chloride catalyst, incontrast, is evident from the data.

Examples 8 to 12 A catalyst system composed of three parts each ofcupric chloride and zinc chloride was deposited from aqueous solution(using the procedure of Example 1) on a series of supports (94 parts ofeach support), which had been crushed where necessary and screened to a10 to mesh size. The catalyst supports were:

Example 8 n-Alumina (Aluminum Company of America, Grade F-l) surfacearea, 210 sq. meters per gram.

Example 9 a-Alumina, as in Example 1.

Example 10 Silica gel Example 11 Titania (Harshaw Chemical Company,Grade Ti-0102-T 56 inch pellets) surface area 70 square meters per gram.

Example 12 Zirconia (Harshaw Chemical Company Grade Zr 0304 T, A inchpellets) surface area 50 square meters per gram.

Each of these supported catalysts was used in the oxychlorination ofethane, using the equipment and procedure set out in Example 1, but atthe temperatures shown in Table IV which follows. The following datawere taken:

It is evident from the data that products consistently high in thedesired l,2-dichloroethane and vinyl chloride reaction products wereobtained, regardless of the support used. Superior yields were obtainedusing catalysts supported on a-alumina, titania and Zirconia, butexcellent results also were obtained on the silica gel and n-aluminacatalysts.

Example 13 An unsupported cupric chloride-zinc chloride catalyst systemwas prepared by evaporation of a common solution of both salts (3 partseach in parts of water) containing 2 parts of concentrated hydrochloricacid. This unsupported catalyst was dispersed in a plug of glass wool,and placed in the reactor used in Example 1. Ethane was thenoxychlorinated over this catalyst, using the reaction conditions ofExample 1. The molar ratio of vinyl chloride plus 1,2- dichloroethane toethyl chloride produced in this process was 10. When the cupricchloride-zinc chloride mixture was replaced with cupric chloride andpotassium chloride, 1.7 parts for each 3 parts of cupric chloride, themolar ratio of the reaction products was only 0.24, showing a depressingeffect of the potassium chloride, in contrast to the enhancing effect ofthe zinc chloride, in the process.

Example 14 An a-alumina, shown to be very pure by X-ray analysis, wasobtained by heating n-alumina (5% inch pellets) at about 1200C. for 16hours. The product had a surface area of 9 square meters per gram. On to94 parts of this a-alumina was deposited a mixture of 3 parts of cupricchloride and 3 parts of zinc chloride, from a common solution in 250parts of methanol and 2.5 parts of concentrated hydrochloric acid. 28grams of this supported catalyst was then employed in theoxychlorination of ethane, following the procedure of Example 7, butvarying the oxygen content of the reactant feed, in accordance with thedata shown in Table V.

Product Amount Recovered (millimoles per hour) C,H,Cl O.l 0.1 0.3 ClC,HCl 11.2 12.4 l8.4 CH CHCI 3.2 3.3 1.3

It is apparent from the above data that an excess of oxygen over thetheoretical amount required for complete hydrogen chloride conversionproved beneficial in this process. Although the ratio of vinyl chlorideplus 1,2-dichloroethane to ethyl chloride decreased somewhat, after aninitial rise, the percent of hydrogen chloride appearing as chlorine inthese three products increased steadily.

Examples and 16 Table VI Mole Ratio: Example Catalyst CICH,CH,

CHZCHCI N0. Combination to C,II,Cl

l5 CuCl,/ZnCl, l0 l6 CuCl,/ZnCl,lMgCl, l0 Control CuClJZnch/KCI 0.5

It is evident from the data that the addition of magnesium chloridewhich serves to repress volatility does not in any way modify theselectivity of the copper chloride-zinc chloride catalyst system. On theother hand, potassium chloride definitely upsets selectivity, resultingin a negligible proportion of 1,2- dichloroethane and vinyl chloride toethyl chloride.

Example 17 This example illustrates the oxychlorination of ethylchloride.

28 grams of the cupric chloride-zinc chloride catalyst system of Example14 was used in the oxychlorination of ethyl chloride. The reactor usedwas that described in Example 7, modified to allow a feed of ethylchloride mixed with nitrogen in the feed ratio ethyl chloride/hydrogenchloride/oxygen/nitrogen of 25.8/25.8/l2.9/25.8 ml. per minute. Yieldsof vinyl chloride plus l,2-dichloroethane of 62 to 86 percent wereobtained, at temperatures within the range of 275 to 325C, at 75 to 95percent conversions of the ethyl chloride.

For comparison purposes, ethyl chloride also was oxychlorinated using acupric chloride-potassium chloride catalyst prepared by depositing onto95.3 parts of the a-alumina of Example 14 a solution containing threeparts cupric chloride and 1.7 parts potassium chloride, according to theprocedure of Example 7. The reactor of Example 7 was also used, at thesame 0 an appreciable reduction of reaction temperature.

Example 18 This example illustrates a two-stage oxychlorination,

the first stage of ethane, and the second stage of the ethyl chloriderich product stream from the first stage. A separate catalyst system wasused for each of the two reaction stages, in the first stage one basedon cupric chloride-potassium chloride for the conversion of ethane toethyl chloride as a major product, and in the second stage one based oncupric chloride-zinc chloride for the conversion of ethyl chloride (withresidual ethane) from the first stage to 1,2- dichloroethane and vinylchloride as major products. The catalyst systems used were thosedescribed in Example l7, and the reactor was that of Example 7. In thepresent experiment, the reactor was packed with ll grams of the cupricchloride-potassium chloride catalyst system (first stage) followed by 17grams of the cupric chloride-zinc chloride catalyst system (secondstage) and placed in a single tube heater at 325C. Reactants wereentered at a 4/2/1 ratio of ethane/hydrogen chloride/oxygen and a totalflow rate of 209 millimoles per hour.

To define the amounts of ethyl chloride, 1,2- dichloroethane and vinylchloride produced in the first stage and subsequently fed in thereactant stream to the second stage, the products of the first stageonly (cupric chloride-potassium chloride catalyst system) were analyzedseparately, and the analyses obtained are given in Table VII. Theproducts of the combined two stages also were analyzed, and the analysesobtained also are given in Table VII. It is apparent from the data ofTable VII that ethyl chloride produced in the first stage reactionthereafter is converted to 1,2- dichloroethane-vinyl chloride productsin the second stage reaction in excellent yield as a continuous processwithout intermediate purification of the first stage product stream.

Example 19 Example 18 was repeated except that the ethanehydrogenchloride-oxygen react-ant stream was fed to the reactor at a total rateof 312 millimoles per hour thus reducing residence time in both reactionstages. Analyses of the products of the two stages again are contrastedin Table VII. It is apparent from the data of Table VII that, inaddition to ethyl chloride produced in the first stage, ethaneunconverted in the first stage was converted to 1,2-dichloroethane-vinylchloride products in the second stage.

Table VII Two Stage Oxychlorination of Ethane Example 18 Example I9 1ststage 2 stage Ist stage 2 stage only process only processCatalyst-Cocatalyst First Stage CuCl CuCl,/ CuClJ CuCl,/ KCI KCI KCI KCISecond Stage none CuClJ none CuCl,/

ZnCl, ZnCl, Reactant Gases (M Mole/Hr.) 209 209 3l2 312 Product or RatioEthyl Chloride l2.4 0.6 7.1 0.7 (M Mole/Hr.) 1,2-Dichloroethane 0.7 12.00.2 13 .2 (M Mole/Hr.) Vinyl Chloride 0.6 0 0.8 (M Mole/Hr.) Mole Ratioof 0.56 2] 0.028 20. ClCH,CH,Cl CH,CHCI to C,H,Cl

It is apparent from the data of Table VI! that ethane can beoxychlorinated in two stages as well as in single stage processes suchas were illustrated in Example 7. Furthermore, it is apparent fromcomparison of Examples l8 and 19 that the invention is applicableequally both to ethane and to ethyl chloride and as well to theirmixtures one with the other and with other oxychlorinati on products ofethane.

Having regard to the foregoing disclosure, the following is claimed asthe inventive and patentable embodiments thereof:

1. A process for the preferential oxychlorination of ethane and/or ethylchloride as a reactant to form 1,2- dichloroethane as the major reactionproduct, which comprises feeding the reactant ethane and/or ethylchloride in the vapor phase in admixture with hydrogen chloride in anamount within the range from about 0.05 to about equivalents per mole ofthe reactant and with molecular oxygen in an amount within the rangefrom about 0.2 to about 1.5 moles per equivalent of hydrogen chloride incontact with a catalyst consisting essentially of a copper chloride anda Group Ilb metal chloride in an amount within the range from about 20to about mole percent based on the moles of copper, at a temperaturewithin the range from 250 to 400C, and recovering l,2,-dichloroethane asthe major reaction product.

2. A process in accordance with claim 1 in which the reactant is ethaneand the major reaction product is l ,2-dichloroethane.

3. A process in accordance with claim 1 in which the mixture of gaseousreactant comprises an amount of hydrogen chloride within the range fromabout 0.1 to about 1 equivalent per mole of the reactant.

4. A process in accordance with claim 1 in which the catalyst comprisescopper chloride in combination with an amount of a Group ll b metalchloride within the range from about 30 to about 60 mol percent.

5. A process in accordance with claim 1 wherein the Group II b metalchloride is zinc chloride.

6. A process in accordance with claim 1 wherein the Group Ilb metalchloride is cadmium chloride.

7. A process in accordance with claim 1 in which the catalyst issupported on an inert carrier.

8. A process in accordance with claim 1 in which the reactant is ethylchloride.

9. A process in accordance with claim 1 in which the oxygen is suppliedas air.

10. A process in accordance with claim 1 in which the proportion ofoxygjen in the reaction mixture is within t e range from a out 0.2 toabout 1.5 moles per equivalent of hydrogen chloride.

11. A process in accordance with claim 1 in which the contact time withthe catalyst is within the range from about 0.1 to about 50 seconds. I

1. A PROCESS FOR THE PREFERENTIAL OXYCHLORINATION OF ETHANE AND/OR ETHYLCHLORIDE AS A REACTANT TO FORM 1,2-DICHLOREETHANE AS THE MAJOR REACTIONPRODUCT, WHICH COMPRISES FEEDING THE REACTANT ETHANE AND/OR ETHYLCHLORIDE IN THE VAPOR PHASE IN ADMIXTURE WITH HYDROGEN CHLORIDE IN ANAMOUNT WITHIN THE RANGE FROM ABOUT 0.05 TO ABOUT 5 QUIVALENTS PER MOLEOF THE REACTANT AND WITH MOLECULAR OXYGEN IN AN AMOUNT WITHIN THE RANGEFROM ABOUT 0.2 TO ABOUT 1.5 MOLES PER EQUIVALENT OF HYDROGEN CHLORIDE INCONTACT WITH A CATALYST CONSISTING ESSENTIALLY OF A COPPER CHLORIDE ANDA GROUP II B METAL CHLORIDE IN AN AMOUNT WITHIN THE RANGE FROM ABOUT 20TO ABOUT 70 MOLE PERCENT BASED ON THE MOLES OF COPPER, AT A TEMPERATUREWITHIN THE RANGE FROM 250* TO 400*C. AND RECOVERING 1,2-DICHLOROETHANEAS THE MAJOR REACTION PRODUCT.
 1. A process for the preferentialoxychlorination of ethane and/or ethyl chloride as a reactant to form1,2-dichloroethane as the major reaction product, which comprisesfeeding the reactant ethane and/or ethyl chloride in the vapor phase inadmixture with hydrogen chloride in an amount within the range fromabout 0.05 to about 5 equivalents per mole of the reactant and withmolecular oxygen in an amount within the range from about 0.2 to about1.5 moles per equivalent of hydrogen chloride in contact with a catalystconsisting essentially of a copper chloride and a Group IIb metalchloride in an amount within the range from about 20 to about 70 molepercent based on the moles of copper, at a temperature within the rangefrom 250* to 400*C, and recovering 1,2-dichloroethane as the majorreaction product.
 2. A process in accordance with claim 1 in which thereactant is ethane and the major reaction product is 1,2-dichloroethane.3. A process in accordance with claim 1 in which the mixture of gaseousreactant comprises an amount of hydrogen chloride within the range fromabout 0.1 to about 1 equivalent per mole of the reactant.
 4. A processin accordance with claim 1 in which the catalyst comprises copperchloride in combination with an amount of a Group II b metal chloridewithin the range from about 30 to about 60 mol percent.
 5. A process inaccordance with claim 1 wherein the Group II b metal chloride is zincchloride.
 6. A process in accordance with claim 1 wherein the Group IIbmetal chloride is cadmium chloride.
 7. A process in accordance withclaim 1 in which the catalyst is supported on an inert carrier.
 8. Aprocess in accordance with claim 1 in which the reactant is ethylchloride.
 9. A process in accordance with claim 1 in which the oxygen issupplied as air.
 10. A process in accordance with claim 1 in which theproportion of oxygen in the reaction mixture is within the range fromabout 0.2 to about 1.5 moles per equivalent of hydrogen chloride.